Hitachi ZAX870(P/N:4638433) carrier roller/excavator undercarriage system/china carrier/upper roller factory

Product Specifications

Hitachi ZAX870(P/N:4638433) drive sprocket rim/excavator undercarriage system/china sprockets factory/DPW-parts manufacture top quality spare part.

The ZAX870 is a large hydraulic excavator from Hitachi (now Hitachi Construction Machinery, HCM). The top roller (carrier roller) is a crucial undercarriage component that supports the excavator’s track chain and ensures smooth movement.

1. What is a Top/Carrier Roller?

• Function: Supports the upper part of the track chain, reducing sag and maintaining proper track tension.

• Location: Mounted on the upper frame (carrier) of the undercarriage.

• Key Features:

  • Sealed and lubricated for long life.

  • Made from hardened steel to resist wear.

  • May have flanges to prevent track derailment.

2. ZAX870 Roller Specifications

• Compatibility: Must match the ZAX870 model (confirm exact variant, e.g., ZAX870-3, ZAX870-5, etc.).

• OEM Part Numbers: Example: 418-XX-XXXX (varies by model year).

• Aftermarket Alternatives: Many manufacturers produce compatible rollers.

3. Signs You Need a Replacement

• Excessive play or wobbling (bearing failure).

• Visible wear or flat spots on the roller surface.

• Oil leaks (seal damage, leading to lubrication loss).

• Track misalignment (uneven roller wear).

4. Where to Buy ZAX870 Top/Carrier Rollers

OEM Parts (Hitachi Genuine)

• Hitachi/HCM dealers (best for exact fit, but costly).

• Part Number Example: Check service manuals or dealer listings.

Aftermarket Options (More Affordable)

• CQCtrack/DPW-parts – High-quality undercarriage parts.

• Undercarriage Specialists:

  • Vema Track

  • Track Shop

  • Finning (CAT, but carries some HCM parts)

Online Marketplaces

• CQCtrack&DPW-parts – For factory new rollers.

• Local heavy equipment parts suppliers – May offer rebuilt options.

5. Replacement Tips

✔ Inspect the entire undercarriage (sprockets, idlers, track chain).
✔ Use proper lifting equipment – Rollers are heavy!
✔ Check track tension after replacement.
✔ Torque bolts to spec (prevents loosening under vibration).

Next Steps

• Confirm your ZAX870 model & serial number (critical for correct parts).

• Compare OEM vs. aftermarket (cost vs. durability).

• Check if buying individual rollers or a full set is more economical.

Would you like help finding a specific supplier or part number? Let me know!